Subject: Re: [patch 1/1] drivers/net/ethernet/marvell/mvmdio.c: Fix non OF case

From: Arnaud Patard (Rtp) <[email-masked]>
Date: Fri, 02 Aug 2019 18:21:07 +0200

Andrew Lunn <[email-masked]> writes:

Hi,

> On Fri, Aug 02, 2019 at 10:32:40AM +0200, Arnaud Patard wrote:
>> Orion5.x systems are still using machine files and not device-tree.
>> Commit 96cb4342382290c9 ("net: mvmdio: allow up to three clocks to be
>> specified for orion-mdio") has replaced devm_clk_get() with of_clk_get(),
>> leading to a oops at boot and not working network, as reported in 
>> https://lists.debian.org/debian-arm/2019/07/msg00088.html and possibly in
>> https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=908712.
>> 
>> Link: https://lists.debian.org/debian-arm/2019/07/msg00088.html
>> Fixes: 96cb4342382290c9 ("net: mvmdio: allow up to three clocks to be specified for orion-mdio")
>> Signed-off-by: Arnaud Patard <[email-masked]>
>> Index: linux-next/drivers/net/ethernet/marvell/mvmdio.c
>> ===================================================================
>> --- linux-next.orig/drivers/net/ethernet/marvell/mvmdio.c
>> +++ linux-next/drivers/net/ethernet/marvell/mvmdio.c
>> @@ -319,20 +319,33 @@ static int orion_mdio_probe(struct platf
>>  
>>  	init_waitqueue_head(&dev->smi_busy_wait);
>>  
>> -	for (i = 0; i < ARRAY_SIZE(dev->clk); i++) {
>> -		dev->clk[i] = of_clk_get(pdev->dev.of_node, i);
>> -		if (PTR_ERR(dev->clk[i]) == -EPROBE_DEFER) {
>> +	if (pdev->dev.of_node) {
>> +		for (i = 0; i < ARRAY_SIZE(dev->clk); i++) {
>> +			dev->clk[i] = of_clk_get(pdev->dev.of_node, i);
>> +			if (PTR_ERR(dev->clk[i]) == -EPROBE_DEFER) {
>> +				ret = -EPROBE_DEFER;
>> +				goto out_clk;
>> +			}
>> +			if (IS_ERR(dev->clk[i]))
>> +				break;
>> +			clk_prepare_enable(dev->clk[i]);
>> +		}
>> +
>> +		if (!IS_ERR(of_clk_get(pdev->dev.of_node,
>> +				       ARRAY_SIZE(dev->clk))))
>> +			dev_warn(&pdev->dev,
>> +				 "unsupported number of clocks, limiting to the first "
>> +				 __stringify(ARRAY_SIZE(dev->clk)) "\n");
>> +	} else {
>> +		dev->clk[0] = clk_get(&pdev->dev, NULL);
>> +		if (PTR_ERR(dev->clk[0]) == -EPROBE_DEFER) {
>>  			ret = -EPROBE_DEFER;
>>  			goto out_clk;
>>  		}
>
> Hi Arnaud
>
> It is a long time since i looked at Orion5x. Is this else clause even
> needed? If my memory is right, i don't think it needs to enable tclk?
> It was kirkwood which first added gateable clocks. And all kirkwood
> boards are not DT.

I was not sure if the else clause was needed or not so I only restored
similar behaviour to what was there before the commit 96cb4342382290c9.

By looking at the commit logs, the commit adding the clock support
3d604da1e9547c09 (net: mvmdio: get and enable optional clock) doesn't
mention the SoC names. So, I've no idea if it's needed or not.

Arnaud